Tractor lug



H. GRIEBAT TRACTOR LUG Jan. 3, 1933.

Filed March 14, 1932 INVENToR BY Qvmgy Patented Jan. 3, 1933 UNELED STATES PATEN TRACTOR LUG Application led March 14, 1932. Serial No. 598,596.

This invention relates to tractors lugs or carriers such as are applied to round wheel tractors in order to increase their traction.

The principal object of my invention is to provide a lug of this general character so constructed that each time it pulls out of the ground it will shake od and clear itself of any dirt tending to adhere in the angle between the wheel rim and the lug, so that my improved lug may truly be defined as being self-cleaning.

A further object is to construct the lug so that when traveling over hard ground it provides a cushioning effect on the tractor, thus reducing shocks and vibrations otherwise imparted to the tractor and promoting the comfort ot the operator in giving easier or softer riding qualities to the tractor.

A further object of the invention is to produce a simple and inexpensive device and yet one which will be exceedingly effective for the purpose for which it is designed.

The objects I accomplish by means ot such structure and relative arrangement of parts as will fully appear by a perusal of the tollowing specification and claims.

In the drawing similar characters of reterenee indicate corresponding parts in the several views:

Fig. l is a side view ot my improved lug as mounted on a wheel and as supporting the weight of the tractor.

Fig. 2 is a .similar view with the near side of the sheath removed as on the line 2 2 of Fig. 4.,

Fig. 3 is a view similar to Fig. 2 with the lug relieved ot its load.

Fig. i is a front view of the lug` partly broken away and with the load on the lug.

Fig. 5 is a sectional plan taken on the line 5-5 ot Fig. t.

Fig. 6 is a perspective view ot the inner body or core et the lug.

Referring nov.r more particularly to the characters ot reference on the drawing, the inner member or tiXed core ot the lug comprises a base l of rectangular torni and curved on one :tace to Jfollow the curvature of the rim 2 ot the tractor wheel on which said base rests. A. bolt 3 depends centrally from the curved face of the base, said bolt projecting through a hole in the rim and being secured to the rim by a nut li. T he portion of the bolt engaging the rim is non-circuv lar, as is the hole, so that the bolt and base t cannot turn.

Projecting trom the opposite tace of the base is the body 5 ot the core, the side edges of the body being parallel to each other and tlush with the sides of the base. The opposite faces however preferably have an inception some distance from the corresponding edges of the base and extend in converging relation to each other so that the body is of wedge-like form and` is correspondingly very "1 strong in the direction trom which the strains come -Jithout being excessively heavy. At the sides of the body the converging surfaces thereof are cut away diagonally from the F base upwardly to the top, as shown at 6 so as "Q to leave tlat ledges 7 at the base on the opposite sides and corners ot the body.

Slidably mounted on the core is the outer member or sheath of the lug comprising a base 8 larger than the base l and a portion 9 enveloping the body 5. rhe hollow interior area 10 of the sheath extends unbroken from the outer face of the base 8 and is shaped to follow the contour ot the body and cut away portions 6 so that the base 8 may be supported o on the ledges 7 of the core. rl'he size ot the area 10 relative to that of the core body is such that when the sheath thus rests on the ledges the adjacent walls of the core and sheath are still clear et each other slightly, S" as indicated in Fig. 5 so that there is no tendency tor the separate parts to bind and wedge each other.

In normal operation however he base 8 never engages said ledges since the base rides on a compressible pad 1l. of suitable material which rests on theriin 2 in surrounding relation to the base l and which in its normal un compressed condition is considerably thicker than said base. as shown in Fig. 3. i

The sheath is prevented from dropping oit the core when inverted by pins in the term of cap screws l2 mounted in the sides ot the sheath and whose inner ends project into notches i3 cut in the sides of the core lengthwise thereof or radially of the wheel.v The length of the notches is suficient to permit of the necessary radial movement of the sheath Afrom the uncompressed position of the pad to a position at which the, pad is fully compressed and the sheath base rests on the ledges.

In operation it will be seen that as long as the sheath clears the ground it is held outwardly relative to the core by the expanding pressure of the pad. -When `the sheath engages the ground the pad is compressed and the shocks and jars otherwise imparted to the Wheel and tractor by the sudden contact of the lug with hard ground is absorbed by the cushion pad. When the lug again draws out of the .ground the pad expands, pushing the sheath outwardly and breaking loose any7 dirt which may have been lodged between the lug and the rim of the wheel. The base of the sheath is always engaged with the pad, which extends all about the base so that no dirt can enter between the parts and cause 'a clogging or wedging action. Any time it is necessary to replace a pad in the event that 'it has deteriorated this may be done either by removing the lug in toto by taking off the nut ll, or by removing the pins l2 so as to withdraw the sheath alone. Either operation of course will expose the pad for removal. f

It is to be noted that thevpins l2 engage the corresponding ends of the notches before a fully uncompressed condition of the pad is reached, so that the remaining pressureof vthe pad not only prevents rattling of the sheath on the core, but holds kthe base 8 in constant and closeengagement with the pad. I also preferably bevel off the fore and aft edges of the pad about the central opening as shown, so as to prevent said edges, when .the pad is being compressed, from possibly squeezing in between the core and sheath and causing the latter to jam.

From the foregoingdescriptionit will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set vforth herein. y

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from .such detail may be resorted to as do not form a departure from the spirit of the invention,

I as defined by the appended claims.

Having thus described my invention what I claim as new and useful and desire to secure by lLetters Patent is: v

1. A tractor lug including a lcore member to project radially from the tread face of a wheel, means'to rigidly secure the core on the wheel, a .ground engaging sheath slidably mounted on and covering the core, means to limit radially outward sliding movement of the sheath, and a resilient cushion element supported on said wheel face and disposed between the base of the sheath and the wheel to normally hold the sheath outwardly of the wheel.

2. A tractor lug including a core member to project radially from the tread face of a Wheel, means to rigidly secure the core on the wheel, a ground engaging sheath slidably mounted on and covering the core, means to limit radially outward sliding movement of the sheath, and a continuous resilient pad supported on said .wheel face and surrounding the bas-e of the core the base of the sheath resting throughout its peripheral extent on said pad.

' 3. A device as in claim 1, with shoulders formed on the core adjacent its base to engage the base of the .sheath after the pad has been compressed a predetermined amount.` i

4. A tractor lug including alcore member to project radially from the tread face of a wheel, means Vto rigidly secure the core on the wheel, a ground engaging sheath slidably mounted on and covering the core, the latter having a longitudinal slot intermediate its ends permanently covered by the sheath, a

pin mounted in the sheath and engaging the slot, and a resilient element disposed between the base of the sheath and the wheel to normally hold the sheath .outwardly of the wheel.

In testimony whereof I aliix my signature.

HERMAN GRIEBAT. 

